In many applications, it is necessary to mount electrical cables to terminals or connector housings and to seal the connection against moisture or dust etc. To this end so-called single wire seals are known in the art, which are arranged onto the cable sheath and which provide a seal between the cable and inner walls of the terminal or the connector housing.
The elastic single wire seal is commonly attached to the electric cable and in particular by means of the crimping means of electrical contact terminals provided at the end of the cable. Thereby, the seal is securely fixed to the cable. However, since the sealing member, i.e. the single wire seal, is made of a highly elastic material, the crimping may lead to severe deformations of the single wire seal. These deformations do not only impair the sealing properties of the single wire seal, but also have the effect that the minimum pull force requirements between the single wire seal and the electric cable are no longer met. Thereby, a loosening of the crimped connection between the electric cable and the single wire seal may occur during handling of the cable or when pulling the crimped terminal out of a housing.
A typical prior art document dealing with the crimping of elastic single wire seals is DE 3904069 A1. This document discloses a waterproof plug for a connector. The waterproof plug comprises a rubber plug having an outer tube portion capable of fitting to an inner wall of a connector housing, a stabilizing tube rigidity mounted next to the outer tube portion of said rubber plug, and an electric wire inserting hole in the central portion thereof.
A further prior art document dealing with elastic single wire seals is DE 19828482 A1. This document discloses a single wire seal for sealing a gap between a conductor and a connector chamber. A reinforcement region is joined to a sealing region of a sealing body. Further, reinforcement ribs are connected on a first side to a hollow cylindrical base of the reinforcement region, and on an adjacent second side to a sealing lip.
However, the number of electric devices loaded on e.g. vehicles recently increased and therefore smaller sizes of electrical contact elements and connector housings are demanded. As the negative influence of the crimping on the sealing properties and the minimum pull force requirements is even worse for small single wire seals a huge demand exists for further improved single wire seals and in particular for single wire seals adapted for relatively thin cables.
Although single wire seals are not expensive components, they are mass products and have therefore a considerable influence on the production quality and the production costs of a large number of products. Therefore, it is important to optimize the manufacture of such single wire seals to reduce the manufacturing costs while, at the same time, securing a tight and sufficient fit in a connector housing.